For centuries people have been
attempting to make order out of the vast number of plants that
exist in our world. In the most accepted organizational system,
binomial nomenclature, there are many different levels.
For the home gardener, it is
generally useful to know at least four of these levels. We start
with the plant family which consists of a
large group of plants
that have a small number of characteristics in common. The genus
(plural is genera) is a subdivision of the family and represents
plants with several more common features. The species consists
of plants that share several key characteristics and will freely
interbreed with each other. The final level is the variety which
is a naturally occurring variation of the species. When these
are brought into cultivation, they are named and called
cultivars. These plants are identical to each other.
Another naming system exists
which consists of common names. The problem with them is that
they can be different in different parts of the world. The
botanical or scientific name of a plant in the binomial
nomenclature system will be the same throughout the world. This
helps avoid a lot of confusion.
Since this site is devoted to
ornamental landscape plants we have generally only included
plant generas which either survive or are used as annuals in the
temperate regions of the world.
The buttons at the top of the
page will take you to
an index of all the families and genera featured by